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Tuesday, April 01, 2008

The Black Hole Bomb

WASHINGTON, April 1st 2008

After more than half a century of research, scientists could finally have made the breakthrough the world has been waiting for: a tactic weapon more devastating than the nuclear bomb, but without its side effects.

"It's clean, it's easy, it erases a town within seconds and leaves nothing than a crater," one of the scientists could be heard saying on a hastily arranged inofficial meeting that took place yesterday.

Construction plans are discussed, the physical principles are clear, but so far no tests have been made. The central ingredient is the creation of a mini-black hole by colliding highly accelerated protons, though L.H. Cee said "We are still working on getting the accelerator into a more handy size." Once created, the black hole will start growing, and suck in its surrounding until it becomes too heavy and sinks to the middle of the earth. Thereby, the actual size of the black hole remains tiny compared to the area it erases, leaving nothing but an crater with a small hole in the middle that can easily be covered to make the ground habitable again.

Critical voices mention the hole would cross the center of the earth and come out on the opposite side. "We can not exclude this possibility," Cee said, "But 71% of the Earth's surface is covered with water, and the risk of losing some jellyfish should not delay world peace."

Haven’t you heard the latest, black holes are of minor concern. Prof. Alfred E. Newman out of Equidaedung University has just written a paper which appears to have solved the dark matter mystery. He indicates that all the dark matter is actually simply the residue of all the extraterrestrial civilizations to have turned on their own LHC(s). Apparently all was turned to strange matter. Upon hearing the news SETI has also announced it will discontinue its search for intelligent life elsewhere in the cosmos, as it now appears such a discovery to be very unlikely. Dr. Jill Tarter says she will no longer contend that there must be other life, as it would be a terrible waste of space, since it turns out it probably is.

Hello,it may be a bit strange to ask a real question in such a thread, but today on april 2nd I dare to ask:What would a "small" black hole do crossing the earth? It should not, of course, be so small to evaporate before it crossed the earth. Would it "eat" a tunnel?Georg

nothing. it would go through and out the other side. it has a diameter roughly 10^-3 fm, the cross-section is tiny, the gravitational attraction completely negligible, and the probability that it accidentally hits even an electron in an atom is negligible. further, not that you said so, but it wouldn't stop in the middle of the earth. i don't know why people seem to have this funny idea. if the initial energy is high enough it would go straight through and bye-bye into outer space. best,

Good point - the escape velocity for the black hole is 11.2 km/s, the same as for any ordinary canon ball or satellite, or β = v/c ≈ 0.00004. That's tiny for high-energy collision kinematics, and most reaction products will easily exceed this number by orders of magnitude (hum... maybe some actual estimates are around somewhere?). Earth' gravity can not trap the particles created in the collision.

Moreover, even though the centre of mass frame of the colliding protons at the LCH is at rest with respect to the detectors, this is generally not the case for the pair of colliding partons that creates the black hole. The black holes will have quite large momenta along the beam axis. Technically speaking, the rapidity distribution should be quite broad (Do you know of actual plots? I remember only transverse momentum plots?).

So, the argument "the black hole is created in the rest frame of the Earth and this is completely different from the situation with cosmic ray events" is an oversimplification that misses essential physics.

This April Fool's post was too easy to see through... However if you'd just said that the pentagon had heard about the concerns over a black hole at the LHC and had assembled a team to determine if one could be used as a weapon... heck, that's probably true!

"If we want to solve a problem that we have never solved before, we must leave the door to the unknown ajar,"Richard Feynman

"A Novel approach" can be in fiction, Why not? :)

ON a previous thought regarding Mission Impossible III(this was sometime ago before the writer's inception into film,) the Ipod now instead of the tape recorder, melts into a superfluid state.

The information(dark energy) was a powerful motivator for the new mission taken on by Tom Cruise..... but wait.....maybe he and the garbage container that he threw the IPod into, was somehow sucked into the hole and spewed out as some new universe along with the new mission?:)

You are joking now, but in the future I imagine, planet-sized black holes will be the weapon of choice of any advanced space-faring civilization. They have a lot going for them:

1. Compact.2. Stealthy.3. Unstoppable.4. The best matter-to-energy conversion rate this side of antimatter.

Perhaps the best approach would be to launch a planet/asteroid towards an enemy space fleet and compress it in-flight somehow. Storing black holes for extended periods of time seems to be fraught with danger.

I'm not sure I trust your safety study. If you made a BH big enough to fall through the Earth before it exploded (say 10^7 kg) it would be pretty hot - roughly a million-billion (10^18) Watt light bulb. During it's day or so of life it would release all of its energy as radiation - about 10^26 J - well below the amount needed to totally disrupt the planet, but likely enough to melt most of it.

If you made it even bigger, to cool it down, say 100 Watts (say 10^14 kg), the gravitational capture cross section in rock becomes inconveniently large.

“the gravitational attraction completely negligible, and the probability that it accidentally hits even an electron in an atom is negligible. further, not that you said so, but it wouldn't stop in the middle of the earth.”

You are of course correct that any black hole (unlikely to be stable) would not only escape earth’s gravity well, yet the solar systems and perhaps the galaxies. However, It is interesting to imagine one without momentum that would thus be influenced by earth’s gravity. If it did not interact with any thing else, say as a neutrino it would come out the other side at the same height above the earth after passing through the centre. What I find interesting is the path traced, relative to the earth’s interior would be dependant on where it started. That is the only straight path through would be if it fell through at one of the poles where the earth’s rotation could be disregarded. Any other point would have the path to be that of a wave shape of one complete cycle with the location where it entered only effect the amplitude of the wave form, not the wave length or frequency. The amplitude would be highest if dropped in at the equator and diminishing to zero at the poles. All paths of course would pass through the centre, which marks the mid point of the wave’s cycle. Of course after it passed through it would again fall to repeat another cycle. Anyway, I thought it interesting to imagine this journey and how this path would resemble a wave form.

I don't think that the issues at stake here are completely ridiculous. [I am thinking about the strangelet scenario rather than black holes.] I agree that it's very unlikely that something nasty will happen --- let's say a billion to one in a given year. Since the entire population of the earth would be killed, this is however precisely equivalent to constructing a machine which is likely to kill 6 human beings a year. Is that ok with everyone here?

Well I thought as this is under the "humour category" and on such a auspicious day, why not continue with aspects of the "Superhero versions" and then throw in some thoughts for consideration about the "continuum of expression" while one tackles the singularity? :)

I disliked this artile. It is a lie that will be misleading, becoming rumor, and finally puts many theorists from the developing countries who work on the useless field of black holes into the security problem for attending conferences when they get into the border and are asked for the field of research. This is exactly the same foolishness that is hidden in the name of Nuclear Physics B, where its papers are irrelevant to the title of the journal. Bee, what you try to make fun of will put many innocent researchers into trouble.

“I agree that it's very unlikely that something nasty will happen --- let's say a billion to one in a given year. Since the entire population of the earth would be killed, this is however precisely equivalent to constructing a machine which is likely to kill 6 human beings a year. Is that ok with everyone here?”

Even though I might contend your estimate too large. I would think that many would agree that any preventable death is tragic and should be avoided if reasonable. Let’s take a realized example. Did you know that in 2005 it was estimated by actual occurrence that you ran 1 chance in 2,245,254 of being killed by a lawn mower if you lived in the U.S. . This resulted in 134 death nation wide. Now if the entire world was to have lawn mowers to an equal degree as the U.S., that would be expected to lead to 2,953 deaths globally each year. Of course serious injury is many time higher then this. Perhaps you should first consider this actually occurring and demonstrated risk as well and convince everyone to simply let their grass grow, as to avoid all this needless suffering and death. Of course I haven’t taken into account the numbers who suffer from hay fever that would have their risk increased if we were to do this.

Give me a break. If this 'rumor' spreads, the problem isn't the 'rumor' but the education system. Same applies for 'nuclear' being a general scare word. Not everybody who is a nuclear physicists builds bombs or is radioactive. You don't solve that problem by verbal cosmetics and renaming things. Given that I am convinced it's only a matter of time until many governments realize that in the face of energy shortages the easiest and cleanest way out is nuclear power, there will either have to come a LOT of verbal cosmetics, or some advertisement *err* education program. Best,

i iz hav a theroy for a dark matter bomb if you put super pressure on dark matter it will transfrom into a crystal but inside is 1,000,000,000heroshimas worth of energy wehn releasd it can wipe a planet from existence but it can be controlled so it could wipe out anything any size